Lepton mass and mixing in a simple extension of the Standard Model based on T7 flavor symmetry

Abstract

A simple Standard Model Extension based on $T_7$ flavor symmetry which accommodates lepton mass and mixing with non-zero ${\theta }_{13}$ and CP violation phase is proposed. At the tree- level, the realistic lepton mass and mixing pattern is derived through the spontaneous symmetry breaking by just one vacuum expectation value ($v$) which is the same as in the Standard Model. Neutrinos get small masses from one $SU(2{)}_L$ doublet and two $SU(2{)}_L$ singlets in which one being in $\underline{1}$ and the two others in $\underline{3}$ and ${\underline{3}}^{\ast }$ under $T_7$ , respectively. The model also gives a remarkable prediction of Dirac CP violation ${\delta }_{CP}=172.598^{\circ }$ in both normal and inverted hierarchies which is still missing in the neutrino mixing matrix.

Comments: 23 pages, 6 figures